Safety release pin

ABSTRACT

A safety pin of an inexpensive construction having a break-away portion which gives an indication that an apparatus has been previously operated.

United States Patent [191 Hansen 1 June 4, 1974 1 SAFETY RELEASE PIN [75] Inventor: Arne Hansen, New City, NY.

[73] Assignee: Walter Kidde & Company, Inc., Belleville, NJ.

[22] Filed: Feb. 5, 1973 [21] Appl. No.: 329,614

[52] U.S. Cl 222/153, 222/473, 116/112, 116/114 S, 169/31 R, 292/322 [51] Int. Cl B65d 27/30, 865d 55/06 Field of Search 292/307 R, 321, 320, 322,

292/327; 169/30, 31 R, 31 P; 85/5 R, 8.3;

[56] References Cited UNITED STATES :PATENTS l ,964,() 1 3 6/1934 Wenk 292/320 3,402,435 9/1968 Mcrscr 292/322 X 3,600,027 8/1971 Noland 292/322 3,611,861 10/1971 Schulze... 85/5 R 3,666,016 5/1972 Estes 292/307 R X 3,702,637 11/1972 Bower .1 292/307 R X Primary Examiner-Robert L. Wolfe Assistant Examiner-Richard P. Tremblay Attorney, Agent, or FirmDarby & Darby [57] ABSTRACT A safety pin of an inexpensive construction having a break-away portion which gives an indication that an apparatus has been previously operated.

8 Claims, 6 Drawing Figures SAFETY RELEASE PIN This invention relates to a safety release pin which is constructed with a break-away portion to provide a visual indication as to whether or not an apparatus has been previously operated to dispense the fluid contained therein.

In certain types of apparatus, a safety release pin is utilized which must be removed before the apparatus can be operated to prevent accidental operation of the apparatus. One such type of apparatus is when a fluid or powder is confined and dispensed under pressure, such as a fire extinguisher, insecticide sprayer and the like. In other apparatus, the material need not necessarily be under pressure.

In pressurized apparatus of the type described, the container for holding the fluid or liquid, is provided with a control head. The control head usually has a handle which is moved from one position to another to operate a valve so that the fluid within the container will be dispensed through an outlet opening in the control head. The control head is also often provided with a safety release pin which must be removed before the handle can be operated to dispense the fluid.

The prior art safety release pin is generally of metal and has a ring at the end thereof. The pin passes through the handle and another portion of the control head and it is safety-wired to the control head or another portion of the container so that it will not be lost. The ends of the safety wire are often sealed by a lead seal as a further measure to retain the pin. In this case, to operate the apparatus, it is necessary to break the lead seal and remove the pin so that the handle can be moved to a position such that the fluid can be discharged. In general, the absence of the lead seal provides the best visual indication that the apparatus has been operated to discharge the fluid.

As should be apparent, the prior art safety release pin arrangement is relatively complicated when it is considered that three pieces are needed to achieve the desired function, that is, the pin itself, the safety wire and the lead seal. In many cases, after the apparatus has been operated, the pin is inadvertently replaced and the apparatus is returned to its place of storage. In the case of a fire extinguisher, this is not desirable since it means that a partially or fully discharged extinguisher will be located where a fully charged one should be placed. While periodic visual inspections are made to prevent this from occurring, itsometimes happens that the absence of the metal seal is often hard to detect.

The present invention is directed to an improved safety release pin of simple construction which functions to prevent an apparatus from being operated until the pin is removed and, at the same time, provides a clearly visible indication when the apparatus has been previously used. In accordance with the invention, a pin of a suitable material, such as a molded plastic, is formed with a pair of at least partially resilient, pronged arms having tabs on their respective ends adjacent a weakened section on the arms. Where the control head and handle arrangement previously described are utilized, the arms pass through the handle of the control head with the tabs projecting beyond the handle. The pin, when in its normal position, prevents the handle from being depressed to discharge the contents of the container. When it is desired to operate the apparatus, the pin is withdrawn. When this is done the tabs break off at the weakened sections of the arms, the pin is removed and the handle is depressed to discharge the contents. If the pin is later inadvertently re-inserted into the control head handle, the tabs will no longer be available and will not be visible. This provides a highly visible indication that the apparatus has previously been operated.

It is therefore an object of the present invention to provide a safety release pin of one-piece construction.

Another object is to provide a safety release pin for of one-piece construction which provides a visible indication as to whether or not an apparatus has been previously operated.

It is still a further object to provide a safety release pin for a pressurized container, such as a fire extinguisher, of the breakaway type which provides an indication of when the extinguisher has been operated.

Other objects and advantages of the present invention will become more apparent upon reference to the following specification and annexed drawings, in which:

FIG. 1 is an elevational view, partially in section, showing the top portion ofua fire extinguisher of generally conventional construction;

FIG. 2 is a perspective view of the control head showing the safety pin in position;

FIG. 3 is a cross-section looking along lines 3-3 of FIG. 1;

FIG. 4 is an enlarged fragmentary view of the pin of FIG. 3;

FIG. 5 is a front view of the safety pin; and

FIG. 6 is a plan view of the safety release pin.

Referring to the drawings, there is shown a pressurized apparatus, such as a fire extinguisher, by way of describing one application of the invention. It should be understood, of course, that the invention can be used in various applications, for pressurized or nonpressurized containers. The apparatus comprises a container 10 of metal or other suitable material formed with a tubular neck 11. A control head 13, which can be of metal, plastic or other suitable material, has an O-ring 14 located near its bottom to engage the interior of the neck of the container to form a seal therewith. The control head 13 is held to the container by any suitable arrangement such as a clip or pin, or by a threaded arrangement as shown in FIG. 1. Any other conventional arrangement also can be used.

A syphon tube 16 held in an internal bore 17 in the control head 12 extends downwardly into the container to communicate with the contents, usually in liquid or powder form, which are held under pressure. A valve 22 seats against the upper end of bore 17 to seal it off from a passageway 24 which communicates with an exit port 25 in the control head. The valve also has a stem 28 which rides in a bore 29. The stem 28 extends above the top of the control head. A spring 30 acting against a washer 31, fastened to the top of the stem, for example by a C-ring, and the top of the control head biases valve 22 into a closed position by moving it upwardly to seat against the top of bore 17.

An operating handle 33 is mounted about a pivot 35 at the top of the control head. The handle can be of metal or plastic construction and has a hollow portion at the top thereof whose inner surface is adapted to engage the top of the stem 28 to depress it. When this occurs, the bias provided by spring 30 is overcome and the valve is moved down into the syphon tube, providing communication between the pressurized material in the container'and the exit port 25.

A fixed handle 38 is also mounted on the control head for the operator to hold as he depresses operating handle 33. Operating handle 33 has a downwardly extending ear 39 on each side thereof. The lower portion of each ear 39 has a hole 40. When the extinguisher is not being operated, the holes 40 are aligned with mating holes 41 in the fixed handle 38 (See FIG. 4) and a safety release pin 42 is located through the two sets of holes 40 and 41. Pin 42 prevents handle 33 from being depressed as long as it is in place. It should be understood that the two handles can be of any desired shape. It should be understood that the handle arrangement can be such that the operating handle 38 lies inside or outside of the fixed handle 38. All that is necessary is that there be one fixed member, one movable member and holes on the two members which can be aligned and through which the safety pin can extend.

The safety release pin 42 is of one-piece construction and is preferably molded from a suitable plastic mate rial which hasgood strength characteristics but yet is also somewhat brittle. One suitable material is the socalled ABS type plastic. The pin includes a ring 43 and a stem 45 which extends from the ring. The end of the stem has a cut 46 partially through its length to form a pair ofarms 47a and 47b. The cut 46 widens toward the free end of the arms (see HO. 4) so they can be compressed and will then spring apart when the force is released.

A groove 50 is formed partly around the circumference of each arm 47, at a point intermediate the cut 46, to form a weakened section on each arm. The width of each groove 50 is somewhat wider than the thickness ofa wall ofthe operating handle 33. Beyond the groove 50 toward the free end of each arm a respective tab 52a and 52b is formed. Each tab is generally semicylindrical in shape and decreases in thickness, that is, it tapers downwardly, from a substantially vertical wall 54 adjacen't'a groove 50 to the tip 56 at the end of the arm. The length of the shaft 45 between the point where it joins the ring 43 and the respective vertical walls 54 of the tabs 52 is greater than the distance between the outer surfaces of the outside handle, in this case the movable operating handle 33. As should be apparent, the arms 47 of the stem on each side of the cut 46 are free to bend. The tapered tabs 52 when moved toward each other as the arms 47 are moved closer together present a diameter which is less than the diameter of the holes 40 and 41 in the operating and fixed handles 33 and 38.

To place the safety release pin in its operative position, the tips 56 of the arms 47 are pushed through one of the holes 40 in the operating handle 33. The entry end of the tabs 52 into the hole 40 will compress the arms 47. The arms will stay compressed as they pass through the holes 41 on each side of the fixed handle 38 and as the end 56 of the stem is pushed through the last hole 40 or handle 33. When the pin is pushed all the way into position through the last hole 40 in handle 33, the arms 47 spring apart. Depending upon the length of the shaft of the pin with respect to the handle, the grooves 50 can extend beyond the outside handle, here the operating handle 33, or the portion of the handle surrounding the last hole 40 can snap into the grooves 50 to lock the pin in position. The former arrangement is shown. In either case the pin cannot slide back out through the handle by itself since the vertical wall 54 of the tabs lock against the handle wall. It is also difficult to compress the arms 47 and push the pin back through the holes of the two handles.

With the pin in place, the operating handle 33 cannot be depressed to operate the extinguisher. When it is desired to operate the extinguisher, the pin is pulled by the ring 43. If sufficient force is applied, the weakened section of the stem of the pin, which is at the groove 50, will break away. That is, the tabs 52 will break away and the pin can easily be withdrawn through the two handles 33 and 38. The operating handle 33 can then be depressed to operate the extinguisher.

If someone desires to re-insert the pin into the extinguisher after the tabs 52 have been broken away, the remainning length of the stem 45 will extend substantially only to the wall of handle 33. The two tabs 52 which have been broken off, will not show. This provides a visual indication that the pin has once been removed, meaning that a good possibility exists that the extinguisher has been operated. To increase the visibility of the indication, the pin can be of a contrasting color to the handles. Also, the tabs 52 can be made relatively long.

As should be apparent, the safety pin is of simple one-piece construction which is considerably less expensive than the prior arrangement of pin, wire and seal. In addition, the pin of the present invention provides a visible indication which can be readily observed.

I claim:

1. In combination a tank for holding material,

a normally closed manually operable discharge valve means connected to the tank, said valve including two relatively movable operating members each having a through hole formed therein, said members being in a predetermined position relative to each other with the holes aligned when the valve is in a closed position and which must be moved relatively out of said position to open the valve, safety release pin for passing through the holes of both said members when said members are in said predetermined position to hold them in said position, said pin having a head portion and a stem connected thereto, said stem passing through the holes of said members with a free end having a portion which extends beyond the members which are located between the head and said portion of the free end, the free end of said stem having a longitudinal cut to form a pair of arms each having a projection thereon so that the total overall size of the projections on the arms is larger than the diameter of the hole of at least one of the members, the arms being compressible toward each other across the cut to permit the free end of the stem to be inserted through the holes of said members, the portion of at least one of the arms of said free end extending beyond said members also having a weakened section formed thereon which breaks away when the pin is pulled from the handle with sufficient force by the action of the projections of the arm having the weakened section engaging one of the members, the outer surface of the stem which extends between the head of the pin and the projection being substantially free of protuberances to permit withdrawal of the pin from the holes of the members.

2. Apparatus as in claim 1 wherein said weakened section of said pin includes a groove formed in at least one of said arms, the projection of said one arm comprising a substantially vertical wall adjacent the groove on the section of said arm which breaks away, the portion of a member surrounding its respective hole fitting in said groove and locking against said vertical wall when the arms are released from a compressed conditron.

3. Apparatus as in claim 2 wherein the portion of said arm between said vertical wall and the end of the arm which breaks away from the arm weakened section tapers downwardly toward the end of the arm to facilitate insertion of the armthrough said holes.

4. Apparatus as in claim 1 wherein each said arm has a weakened section comprising a groove formed therein, the projection formed on each arm between the groove and the end of the respective arm to comprise the break away portion, each projectiontapering downwardly toward the end of the respective arm and including a substantially vertical wall adjacent the groove, the portion of said one of the members surrounding its respective hole locking in said grooves and adjacent the walls of the respective projections when the arms are released from a compressed condition.

5. A safety release pin comprising a head having a stem projecting therefrom, the free end of said stem having a substantially longitudinal cut therethrough to form a pair of arms which are compressible toward each other, a groove formed on at least one of said arms to provide a weakened section on the arm, and a tab member formed between the groove of said one arm and the end of the arm, said tab having a substantially vertical wall adjacent the groove and tapering downwardly toward the end of the arm, the outer surface of the stem between the groove and the head being substantially free of protuberances.

6. A pin as in claim 5 wherein each said arm is formed with a groove to provide the weakened section and a tab having a substantially vertical wall adjacent the weakened section and tapering downwardly toward the free end of the respective arm.

7. A pin as in claim 6 wherein the longitudinal cut on the stem is of increasing height toward the ends of the arms.

8. A pin as in claim 7 wherein said head comprises a ring. 

1. In combination a tank for holding material, a normally closed manually operable discharge valve means connected to the tank, said valve including two relatively movable operating members each having a through hole formed therein, said members being in a predetermined position relative to each other with the holes aligned when the valve is in a closed position and which must be moved relatively out of said position to open the valve, a safety release pin for passing through the holes of both said members when said members are in said predetermined position to hold them in said position, said pin having a head portion and a stem connected thereto, said stem passing through the holes of said members with a free end having a portion which extends beyond the members which are located between the head and said portion of the free end, the free end of said stem having a longitudinal cut to form a pair of arms each having a projection thereon so that the total overall size of the projections on the arms is larger than the diameter of the hole of at least one of the members, the arms being compressible toward each other across the cut to permit the free end of the stem to be inserted through the holes of said members, the portion of at least one of the arms of said free end extending beyond said members also having a weakened section formed thereon which breaks away when the pin is pulled from the handle with sufficient force by the action of the projections of the arm having the weakened section engaging one of the members, the outer surface of the stem which extends between the head of the pin and the projection being substantially free of protuberances to permit withdrawal of the pin from the holes of the members.
 2. Apparatus as in claim 1 wherein said weakened section of said pin includes a groove formed in at least one of said arms, the projection of said one arm comprising a substantially vertical wall adjacent the groove on the section of said arm which breaks away, the portion of a member surrounding its respective hole fitting in said groove and locking against said vertical wall when the arms are released from a compressed condition.
 3. Apparatus as in claim 2 wherein the portion of said arm between said vertical wall and the end of the arm which breaks away from the arm weakened section tapers downwardly toward the end of the arm to facilitate insertion of the arm through said holes.
 4. Apparatus as in claim 1 wherein each said arm has a weakened section comprising a groove formed therein, the projection formed on each arm between the groove and the end of the respective arm to comprise the break away portion, each projection tapering downwardly toward the end of the respective arm and including a substantially vertical wall adjacent the groove, the portion of said one of the members surrounding its respective hole locking in said grooves and adjacent the walls of the respective projections when the arms are released from a compressed condition.
 5. A safety release pin comprising a head having a stem projecting therefrom, the free end of said stem having a substantially longitudinal cut therethrough to form a pair of arms which arE compressible toward each other, a groove formed on at least one of said arms to provide a weakened section on the arm, and a tab member formed between the groove of said one arm and the end of the arm, said tab having a substantially vertical wall adjacent the groove and tapering downwardly toward the end of the arm, the outer surface of the stem between the groove and the head being substantially free of protuberances.
 6. A pin as in claim 5 wherein each said arm is formed with a groove to provide the weakened section and a tab having a substantially vertical wall adjacent the weakened section and tapering downwardly toward the free end of the respective arm.
 7. A pin as in claim 6 wherein the longitudinal cut on the stem is of increasing height toward the ends of the arms.
 8. A pin as in claim 7 wherein said head comprises a ring. 